Reliability Study of La- and Al-Doped ZrO₂ Dielectrics for High Density MIMCAP Applications

Reliability investigations of La-doped and Al-doped ZrO2 are performed. Higher doping concentrations are found to decrease the leakage current and increase the breakdown voltage. Time dependent dielectric breakdown characterizations were performed at various temperatures. The role of energetic carriers in the wear-out and breakdown process is demonstrated, supporting the use of power law lifetime models. The breakdown defect density is shown to decrease at higher temperature. Finally, an Arrhenius temperature dependence of the hard breakdown failure times is observed. A resulting apparent zero field activation energy of around 1.9 ± 0.1 eV is found on the three doped dielectrics.